Systematic Name: 2,4-Dioxo-1,4-dihydro-2H-3,1-benzoxazine-7-carboxylic acid
SMILES: O=C(O)c1ccc2C(=O)OC(=O)Nc2c1
InChI: InChI=1/C9H5NO5/c11-7(12)4-1-2-5-6(3-4)10-9(14)15-8(5)13/h1-3H,(H,10,14)(H,11,12) 
InChIKey: LSXSNVAJTUIEHR-UHFFFAOYAV 
Empirical Formula: C₉H₅NO₅
Molecular Weight: 207.1397
H bond acceptors: 6
H bond donors: 2
Freely Rotating Bonds: 1 
Index of Refraction: 1.631
Molar Refractivity: 45.95 cm³
Molar Volume: 128.8 cm³
Surface Tension: 69.3 dyne/cm
Density of 4-Carboxylic-isatoic anhydride (CAS NO.77423-14-4): 1.607 g/cm³

Risk Statements: 36/37/38 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements of 4-Carboxylic-isatoic anhydride (CAS NO.77423-14-4): 26-36/37/39 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection.

  4-Carboxylic-isatoic anhydride (CAS NO.77423-14-4), its Synonyms are 2,4-Dioxo-1,4-dihydro-2H-3,1-benzoxazine-7-carboxylic acid ; 2H-3,1-benzoxazine-7-carboxylic acid, 1,4-dihydro-2,4-dioxo- ; 2,4-Dioxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-7-carboxylic acid ; 2,4-dioxo-2,4-dihydro-1H-benzo[d]; [1,3]oxazine-7-carboxylic acid .